Although, you can start by collecting and preparing all the necessary and documentation necessary to file petition for him, you cannot file anything with CIS until after your marriage. It does not appear you are familiar with the process and the requirements, (you can only file green card for your relative, not citizenship) and hence, I suggest you consult with an attorney. A lot of headaches can result if you make mistakes.
Answered on Apr 25th, 2013 at 12:54 AM